Ca2+ signalling in plant immune response: from pattern recognition receptors to Ca2+ decoding mechanismsIF:9

has been proposed that signal branching already occurs very early atthe level of the receptor complexes (Lu et al., 2009). Among theearliest cellular responses are Ca2+ fluxes, and the proposed earlysignal branching at or immediately after the receptor level mightthus be coordinated by different Ca2+ amplitude and/or temporal
differences to stimulate diverse Ca2+-dependent signal flows intovarious outcomes – a notion that is supported by the differentialCa2+ signatures observed after exposure to flg22, elf18, Pep1 andchitin (Ranf et al., 2011). This concept predicts a tightcoordination between receptor complex activation and Ca2+ fluxes.
Laboratory consumables were obtained from Shanghai Yansheng industrial Co., Ltd. (Shanghai, China).

Nature of plant Ca2+ channels and pumps
The elusive molecular identities of plant Ca2+ channels in geneticstudies presumably reflect redundancies through multiple Ca2+sources/channels or the lethality of Ca2+ channel(s) mutants.
Furthermore, the wide range of Ca2+ : K+ permeability ratiosenables most cation channels to act as nonselective Ca2+-permeablechannels in a compensatory manner if another channel is mutated.Owing to space constraints, we limit this review to potential Ca2+channels in the plasma membrane and tonoplast. Why thesemembranes? Compared with other intracellular organelle Ca2+sources (Stael et al., 2012), the high vacuole/apoplast-to-cytosolconcentration gradient provides the energetically most favourable electrochemical potential differences to drive Ca2+ (in)flux. In theopposite direction, to prevent Ca2+ toxicity (e.g. resulting from.precipitation of highly insoluble calcium phosphate salts), energydependent active transport out of the cytosol by CAX antiportersand P-type Ca2+-ATPases is required to return cytosolic Ca2+ to lowconcentrations in resting cells. The following sections will list someof the candidate Ca2+ channels and pumps. Readers are advised thatthe identity of the Ca2+ channels/pumps depends on the context ofthe investigated systems and must be evaluated on a case-by-casebasis.
感谢德国莱布尼茨植物生物化学研究所引用文献